/*
 * Copyright (c) 2008, 2009 Sun Microsystems. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
 * which accompanies this distribution.
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *     Linda DeMichiel - Java Persistence 2.0 - Version 2.0 (October 1, 2009)
 *     Specification available from http://jcp.org/en/jsr/detail?id=317
 */

// $Id: Query.java 20957 2011-06-13 09:58:51Z stliu $

package javax.persistence;

import java.util.*;

/**
 * Interface used to control query execution.
 *
 * @see TypedQuery
 * @see Parameter
 * @since Java Persistence 1.0
 */
public interface Query {

	/**
	 * Execute a SELECT query and return the query results
	 * as an untyped List.
	 *
	 * @return a list of the results
	 *
	 * @throws IllegalStateException if called for a Java
	 * Persistence query language UPDATE or DELETE statement
	 * @throws QueryTimeoutException if the query execution exceeds
	 * the query timeout value set and only the statement is
	 * rolled back
	 * @throws TransactionRequiredException if a lock mode has
	 * been set and there is no transaction
	 * @throws PessimisticLockException if pessimistic locking
	 * fails and the transaction is rolled back
	 * @throws LockTimeoutException if pessimistic locking
	 * fails and only the statement is rolled back
	 * @throws PersistenceException if the query execution exceeds
	 * the query timeout value set and the transaction
	 * is rolled back
	 */
	List getResultList();

	/**
	 * Execute a SELECT query that returns a single untyped result.
	 *
	 * @return the result
	 *
	 * @throws NoResultException if there is no result
	 * @throws NonUniqueResultException if more than one result
	 * @throws IllegalStateException if called for a Java
	 * Persistence query language UPDATE or DELETE statement
	 * @throws QueryTimeoutException if the query execution exceeds
	 * the query timeout value set and only the statement is
	 * rolled back
	 * @throws TransactionRequiredException if a lock mode has
	 * been set and there is no transaction
	 * @throws PessimisticLockException if pessimistic locking
	 * fails and the transaction is rolled back
	 * @throws LockTimeoutException if pessimistic locking
	 * fails and only the statement is rolled back
	 * @throws PersistenceException if the query execution exceeds
	 * the query timeout value set and the transaction
	 * is rolled back
	 */
	Object getSingleResult();

	/**
	 * Execute an update or delete statement.
	 *
	 * @return the number of entities updated or deleted
	 *
	 * @throws IllegalStateException if called for a Java
	 * Persistence query language SELECT statement or for
	 * a criteria query
	 * @throws TransactionRequiredException if there is
	 * no transaction
	 * @throws QueryTimeoutException if the statement execution
	 * exceeds the query timeout value set and only
	 * the statement is rolled back
	 * @throws PersistenceException if the query execution exceeds
	 * the query timeout value set and the transaction
	 * is rolled back
	 */
	int executeUpdate();

	/**
	 * Set the maximum number of results to retrieve.
	 *
	 * @param maxResult maximum number of results to retrieve
	 *
	 * @return the same query instance
	 *
	 * @throws IllegalArgumentException if the argument is negative
	 */
	Query setMaxResults(int maxResult);

	/**
	 * The maximum number of results the query object was set to
	 * retrieve. Returns <code>Integer.MAX_VALUE</code> if <code>setMaxResults</code> was not
	 * applied to the query object.
	 *
	 * @return maximum number of results
	 *
	 * @since Java Persistence 2.0
	 */
	int getMaxResults();

	/**
	 * Set the position of the first result to retrieve.
	 *
	 * @param startPosition position of the first result,
	 * numbered from 0
	 *
	 * @return the same query instance
	 *
	 * @throws IllegalArgumentException if the argument is negative
	 */
	Query setFirstResult(int startPosition);

	/**
	 * The position of the first result the query object was set to
	 * retrieve. Returns 0 if <code>setFirstResult</code> was not applied to the
	 * query object.
	 *
	 * @return position of the first result
	 *
	 * @since Java Persistence 2.0
	 */
	int getFirstResult();

	/**
	 * Set a query property or hint. The hints elements may be used
	 * to specify query properties and hints. Properties defined by
	 * this specification must be observed by the provider.
	 * Vendor-specific hints that are not recognized by a provider
	 * must be silently ignored. Portable applications should not
	 * rely on the standard timeout hint. Depending on the database
	 * in use and the locking mechanisms used by the provider,
	 * this hint may or may not be observed.
	 *
	 * @param hintName name of the property or hint
	 * @param value value for the property or hint
	 *
	 * @return the same query instance
	 *
	 * @throws IllegalArgumentException if the second argument is not
	 * valid for the implementation
	 */
	Query setHint(String hintName, Object value);

	/**
	 * Get the properties and hints and associated values that are
	 * in effect for the query instance.
	 *
	 * @return query properties and hints
	 *
	 * @since Java Persistence 2.0
	 */
	Map<String, Object> getHints();

	/**
	 * Bind the value of a <code>Parameter</code> object.
	 *
	 * @param param parameter object
	 * @param value parameter value
	 *
	 * @return the same query instance
	 *
	 * @throws IllegalArgumentException if the parameter
	 * does not correspond to a parameter of the
	 * query
	 * @since Java Persistence 2.0
	 */
	<T> Query setParameter(Parameter<T> param, T value);

	/**
	 * Bind an instance of <code>java.util.Calendar</code> to a <code>Parameter</code> object.
	 *
	 * @param param parameter object
	 * @param value parameter value
	 * @param temporalType temporal type
	 *
	 * @return the same query instance
	 *
	 * @throws IllegalArgumentException if the parameter does not
	 * correspond to a parameter of the query
	 * @since Java Persistence 2.0
	 */
	Query setParameter(Parameter<Calendar> param, Calendar value,
                       javax.persistence.TemporalType temporalType);

	/**
	 * Bind an instance of <code>java.util.Date</code> to a <code>Parameter</code> object.
	 *
	 * @param param parameter object
	 * @param value parameter value
	 * @param temporalType temporal type
	 *
	 * @return the same query instance
	 *
	 * @throws IllegalArgumentException if the parameter does not
	 * correspond to a parameter of the query
	 * @since Java Persistence 2.0
	 */
	Query setParameter(Parameter<Date> param, Date value,
                       javax.persistence.TemporalType temporalType);

	/**
	 * Bind an argument to a named parameter.
	 *
	 * @param name parameter name
	 * @param value parameter value
	 *
	 * @return the same query instance
	 *
	 * @throws IllegalArgumentException if the parameter name does
	 * not correspond to a parameter of the query or if
	 * the argument is of incorrect type
	 */
	Query setParameter(String name, Object value);

	/**
	 * Bind an instance of <code>java.util.Calendar</code> to a named parameter.
	 *
	 * @param name parameter name
	 * @param value parameter value
	 * @param temporalType temporal type
	 *
	 * @return the same query instance
	 *
	 * @throws IllegalArgumentException if the parameter name does
	 * not correspond to a parameter of the query or if
	 * the value argument is of incorrect type
	 */
	Query setParameter(String name, Calendar value,
                       javax.persistence.TemporalType temporalType);

	/**
	 * Bind an instance of <code>java.util.Date</code> to a named parameter.
	 *
	 * @param name parameter name
	 * @param value parameter value
	 * @param temporalType temporal type
	 *
	 * @return the same query instance
	 *
	 * @throws IllegalArgumentException if the parameter name does
	 * not correspond to a parameter of the query or if
	 * the value argument is of incorrect type
	 */
	Query setParameter(String name, Date value,
                       javax.persistence.TemporalType temporalType);

	/**
	 * Bind an argument to a positional parameter.
	 *
	 * @param position position
	 * @param value parameter value
	 *
	 * @return the same query instance
	 *
	 * @throws IllegalArgumentException if position does not
	 * correspond to a positional parameter of the
	 * query or if the argument is of incorrect type
	 */
	Query setParameter(int position, Object value);

	/**
	 * Bind an instance of <code>java.util.Calendar</code> to a positional
	 * parameter.
	 *
	 * @param position position
	 * @param value parameter value
	 * @param temporalType temporal type
	 *
	 * @return the same query instance
	 *
	 * @throws IllegalArgumentException if position does not
	 * correspond to a positional parameter of the query or
	 * if the value argument is of incorrect type
	 */
	Query setParameter(int position, Calendar value,
                       javax.persistence.TemporalType temporalType);

	/**
	 * Bind an instance of <code>java.util.Date</code> to a positional parameter.
	 *
	 * @param position position
	 * @param value parameter value
	 * @param temporalType temporal type
	 *
	 * @return the same query instance
	 *
	 * @throws IllegalArgumentException if position does not
	 * correspond to a positional parameter of the query or
	 * if the value argument is of incorrect type
	 */
	Query setParameter(int position, Date value,
                       TemporalType temporalType);

	/**
	 * Get the parameter objects corresponding to the declared
	 * parameters of the query.
	 * Returns empty set if the query has no parameters.
	 * This method is not required to be supported for native
	 * queries.
	 *
	 * @return set of the parameter objects
	 *
	 * @throws IllegalStateException if invoked on a native
	 * query when the implementation does not support
	 * this use
	 * @since Java Persistence 2.0
	 */
	Set<Parameter<?>> getParameters();

	/**
	 * Get the parameter object corresponding to the declared
	 * parameter of the given name.
	 * This method is not required to be supported for native
	 * queries.
	 *
	 * @param name parameter name
	 *
	 * @return parameter object
	 *
	 * @throws IllegalArgumentException if the parameter of the
	 * specified name does not exist
	 * @throws IllegalStateException if invoked on a native
	 * query when the implementation does not support
	 * this use
	 * @since Java Persistence 2.0
	 */
	Parameter<?> getParameter(String name);

	/**
	 * Get the parameter object corresponding to the declared
	 * parameter of the given name and type.
	 * This method is required to be supported for criteria queries
	 * only.
	 *
	 * @param name parameter name
	 * @param type type
	 *
	 * @return parameter object
	 *
	 * @throws IllegalArgumentException if the parameter of the
	 * specified name does not exist or is not assignable
	 * to the type
	 * @throws IllegalStateException if invoked on a native
	 * query or Java Persistence query language query when
	 * the implementation does not support this use
	 * @since Java Persistence 2.0
	 */
	<T> Parameter<T> getParameter(String name, Class<T> type);

	/**
	 * Get the parameter object corresponding to the declared
	 * positional parameter with the given position.
	 * This method is not required to be supported for native
	 * queries.
	 *
	 * @param position position
	 *
	 * @return parameter object
	 *
	 * @throws IllegalArgumentException if the parameter with the
	 * specified position does not exist
	 * @throws IllegalStateException if invoked on a native
	 * query when the implementation does not support
	 * this use
	 * @since Java Persistence 2.0
	 */
	Parameter<?> getParameter(int position);

	/**
	 * Get the parameter object corresponding to the declared
	 * positional parameter with the given position and type.
	 * This method is not required to be supported by the provider.
	 *
	 * @param position position
	 * @param type type
	 *
	 * @return parameter object
	 *
	 * @throws IllegalArgumentException if the parameter with the
	 * specified position does not exist or is not assignable
	 * to the type
	 * @throws IllegalStateException if invoked on a native
	 * query or Java Persistence query language query when
	 * the implementation does not support this use
	 * @since Java Persistence 2.0
	 */
	<T> Parameter<T> getParameter(int position, Class<T> type);

	/**
	 * Return a boolean indicating whether a value has been bound
	 * to the parameter.
	 *
	 * @param param parameter object
	 *
	 * @return boolean indicating whether parameter has been bound
	 *
	 * @since Java Persistence 2.0
	 */
	boolean isBound(Parameter<?> param);

	/**
	 * Return the value bound to the parameter.
	 *
	 * @param param parameter object
	 *
	 * @return parameter value
	 *
	 * @throws IllegalArgumentException if the parameter is not
	 * a parameter of the query
	 * @throws IllegalStateException if the parameter has not been
	 * been bound
	 * @since Java Persistence 2.0
	 */
	<T> T getParameterValue(Parameter<T> param);

	/**
	 * Return the value bound to the named parameter.
	 *
	 * @param name parameter name
	 *
	 * @return parameter value
	 *
	 * @throws IllegalStateException if the parameter has not been
	 * been bound
	 * @throws IllegalArgumentException if the parameter of the
	 * specified name does not exist
	 * @since Java Persistence 2.0
	 */
	Object getParameterValue(String name);

	/**
	 * Return the value bound to the positional parameter.
	 *
	 * @param position position
	 *
	 * @return parameter value
	 *
	 * @throws IllegalStateException if the parameter has not been
	 * been bound
	 * @throws IllegalArgumentException if the parameter with the
	 * specified position does not exist
	 * @since Java Persistence 2.0
	 */
	Object getParameterValue(int position);

	/**
	 * Set the flush mode type to be used for the query execution.
	 * The flush mode type applies to the query regardless of the
	 * flush mode type in use for the entity manager.
	 *
	 * @param flushMode flush mode
	 *
	 * @return the same query instance
	 */
	Query setFlushMode(FlushModeType flushMode);

	/**
	 * Get the flush mode in effect for the query execution.
	 * If a flush mode has not been set for the query object,
	 * returns the flush mode in effect for the entity manager.
	 *
	 * @return flush mode
	 *
	 * @since Java Persistence 2.0
	 */
	FlushModeType getFlushMode();

	/**
	 * Set the lock mode type to be used for the query execution.
	 *
	 * @param lockMode lock mode
	 *
	 * @return the same query instance
	 *
	 * @throws IllegalStateException if the query is found not to be
	 * a Java Persistence query language SELECT query
	 * or a Criteria API query
	 * @since Java Persistence 2.0
	 */
	Query setLockMode(LockModeType lockMode);

	/**
	 * Get the current lock mode for the query.
	 *
	 * @return lock mode
	 *
	 * @throws IllegalStateException if the query is found not to be
	 * a Java Persistence query language SELECT query or
	 * a Criteria API query
	 * @since Java Persistence 2.0
	 */
	LockModeType getLockMode();

	/**
	 * Return an object of the specified type to allow access to
	 * the provider-specific API.  If the provider's query
	 * implementation does not support the specified class, the
	 * <code>PersistenceException</code> is thrown.
	 *
	 * @param cls the class of the object to be returned.  This is
	 * normally either the underlying query
	 * implementation class or an interface that it
	 * implements.
	 *
	 * @return an instance of the specified class
	 *
	 * @throws PersistenceException if the provider does not support
	 * the call
	 * @since Java Persistence 2.0
	 */
	<T> T unwrap(Class<T> cls);
}
